Multiple bi-directional input/output power control system

ABSTRACT

A multiple bi-directional input/output power control system includes a network of functional blocks housed in a single enclosure, providing DC power to one or more DC loads, and providing control and internal pathways, sharing one or more AC and/or DC power inputs. The system feeds back AC power from the DC power source into an AC input connection, and the fed-back AC power is shared by other AC loads. The system operates at least one alternative source of DC in a dynamic manner, allowing maximization of power generating capability at respective specific operating conditions of the moment. Power isolation may be handled by an AC isolation block right at a power input. Therefore all other blocks within a multi-function power control unit (MFPCU) are isolated from AC ground.

FIELD OF THE INVENTION

The present invention relates to electrical power units for use insharing and connecting AC alternating current and DC direct currentelectrical power supplies.

SUMMARY OF THE INVENTION

The Multi-Function Power Control Unit (MFPCU) of this invention is anetwork of functional blocks housed in a single enclosure to provide DCpower to one or more DC loads. It provides control and internal pathwaysto share or select a variety of power inputs including AC utility power,alternative DC power sources, as well as DC power from external energystorage devices. Additionally, the MFPCU can also feed back AC powerfrom other attached DC sources into the AC input connection to be sharedby other AC loads (including other MFPCU's) within the enterprise. Thefunctional blocks are implemented as hard wired electronic circuitboards, as software running on an internal digital processor, or as acombination of both types using state-of-the-art design techniques.

The multi-function power control unit includes the following functionalblocks within its enclosure: a digital processor, a low voltage ON/OFFcontrol block, an alternate DC source DC/DC converter, a DC isolationblock, and a bi-directional AC/DC power supply with a bi-directionalcontrol module, power factor correction means, and an anti-islandingcontrol block. In addition, the MFPCU has connectors for the following:AC input, DC load, external energy storage device, alternate DC powersource, external control device, and central data acquisition andcontrol. The AC input is typically designed for single phase 208-277 VACat 50 or 60 Hz. Alternatively, the AC input can be designed for threephase 208-480 VAC at 50 or 60 Hz.

The multi-function power control unit operates an alternative source ofDC direct current, in conjunction with an AC source of power or DC powerstorage device, in a dynamic manner that allows maximum power generatingcapability of the alternative source of DC direct current at thespecific operating conditions of the moment. It also can deliver powerin excess of that required by a DC compatible load to the AC source ofpower, DC power storage device, or both in a shared manner.

The system includes three major subsystems:

a Bi-directional Microprocessor-Controlled 4.5 kW AC to DC Power Supply;

a Buck/Boost DC-to-DC Converter with dynamic voltage control; and,

a DC-Based Meter Monitoring of the AC I/O, DC I/O, and internal voltagesand currents, which is based on a unique Metering and Control Module(MCM).

The aforementioned bi-directional AC/DC power supply of the presentinvention includes an AC/DC converter that performs three functionsbased upon signal from Digital Processor, including the following:

1) rectifies AC and provides regulated DC voltage (via DC isolation)when required by the load or Alternate DC source;

2) rectifies AC and provides regulated DC voltage to an external energystorage device; and,

3) inverts DC power from the alternate DC source or external energystorage and sends it back to the AC System.

A power factor correction means adjusts the power factor of the unit toa specified value.

An anti-islanding means including analog and/or digital logic circuitsis used to detect loss of connection to utility grid or externalsynchronization source.

A bi-directional control module includes an analog and/or digital logicdevice that enables the bi-directional power supply to “invert” DCpower. If this module is not installed the unit can only provide theabove noted functions “1” and “2” but cannot provide function “3”.

A DC isolation means electrically isolates DC output from AC input.

The bi-directional power supply powers a DC Load with High Voltage(250-400 Volts). The Direct Current (DC) load is a device that consumespower, such as a lighting ballast; lamp; solid state lighting, such as alight emitting diode (LED); a DC motor; an AC motor with variablefrequency drive (VFD); or an Inverter. The load may feed power backwardsfor short durations, such as during braking of a motor.

A low voltage ON/OFF control shuts down all output circuits via a lowvoltage signal or via wireless communication device. However, anothervariation allows for a variable signal to dynamically control thevoltage of the output circuits.

An alternate DC source DC/DC converter converts output of an alternateenergy source to a voltage level suitable for the DC load. Thisconverter has the ability to dynamically change the operatingcharacteristics of an alternative energy source to permit optimizationof power transfer or for proper interface with an alternative energysource, such as a photovoltaic (PV) device, a wind turbine, a fuel cell,or an engine driven cogeneration device.

In another variation, the converter is used to provide DC power back tothe alternative energy source during periods of inactivity. For example,a wind turbine needs to maintain its direction into the wind, and yawmotors operate during periods of low wind before power production isachievable. Another example is the start-up of a fuel cell orcogeneration system, which may require fuel pumps, cooling pumps orother auxiliary equipment to be running before power production isachievable.

An external energy storage device stores DC power for use in supplyingpower to the DC load and/or alternate energy source, in the event of aloss of AC power, supplementing power to DC load when required, orsupplementing power to AC system. Examples include a high voltagebattery, a low voltage battery with DC/DC converter, a flow Battery, aflywheel, and a capacitor.

A digital processor monitors and controls power delivery to and from allsources and loads. The digital processor provides an interface forproviding data and receiving control signals from the external centraldata acquisition and control unit. It may provide the followingcontrols:

1) dynamic voltage control and/or current control supplied by analternate DC Source;

2) an ON/OFF control of all output circuits;

3) an ON/OFF control for the bi-directional AC/DC power Supply;

4) dynamically change output voltage; and

5) dynamically change voltage of the DC link.

The digital processor also supplies the following data, if requested orrequired by the external central data acquisition and control unit:

1) volts, amps, and/or power delivered/supplied by the bi-directionalAC/DC power supply;

2) volts, amps, and/or power delivered/supplied by the alternate DCsource;

3) volts, amps, and/or power delivered/supplied by the external energystorage device;

4) volts, amps, and/or power delivered/supplied by the load; and,

5) system status, alarms, operating mode (i.e.: start-up, run, powerfailure, shutdown, fault, etc.)

The central data acquisition and control unit is used to provide theability for central control and data collection of multiple power units,via their digital processors. It may be used for enterprise level and/ormulti-building control, such as load management of utility feederservicing multiple buildings.

The performance of the multi-function power control system of thisinvention for supplying a high efficiency lighting system is as follows:At this time, AC input high efficiency T-8 lighting ballasts operate anoverall efficiency of 88%. A high voltage DC ballast is expected tooperate at 94% efficiency. The multi-function power control system unitis expected to achieve a throughput efficiency of 96%. Thus, whencombined, the overall efficiency can be 90%, which is 2% better thancurrent systems. The main reason for the increase is due to the largerscale AC/DC power supply. This is analogous to central power plants witha distribution system being more efficient than the equivalent sum ofmultiple smaller scale power plants.

A larger scale system is also proposed. The current design is for apower unit that is sized to meet the requirements of a single phase 277V lighting circuit (up to 4.5 kW). An upgrade is a three phase unitcapable of supplying multiple lighting circuits, via a DC distributionsystem, and a single interconnection to the AC system. The larger scalesystem can be from 15 to 250 kW.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can best be understood in connection with theaccompanying drawings. It is noted that the invention is not limited tothe precise embodiments shown in drawings, in which:

FIG. 1 is a Block diagram of a multi-function power control unit (MFPCU)of this invention with external attachment blocks.

FIG. 1A is a block diagram of an alternate embodiment of amulti-function power control unit (MFPCU) of this invention withattachment blocks.

FIG. 1B is a block diagram of a second alternate embodiment of amulti-function power control unit (MFPCU) of this invention withattachment blocks.

FIG. 2 is a chart of IV curves for typical solar cells showing maximumpower load line.

FIG. 3 is a Block diagram showing main current flow through the MFPCUfor an AC Sourced High Efficiency Lighting mode.

FIG. 4 is a Block diagram showing main current flow through the MFPCUfor an AC Outage Operation mode.

FIG. 5 is a Block diagram of enterprise with multiple MFPCU's in a PeakShaving Enterprise AC Wheeling mode.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a block diagram of MFPCU 1 with a network of variousfunctional blocks within and connections to other functional blocks atits periphery. bi-directional AC/DC Power Supply 2 is transformerisolated and has a bridge topology which incorporates MOSFETS orpreferably IGBT's (insulated gate bipolar transistors) which permitoperation as both a synchronous rectifier for supplying DC as well as aninverter to supply AC at its input from DC sources. bi-directionalControl Module 3 controls the operation as to direction, while PowerFactor Control Means 4 insures that power factor at the AC input remainsessentially at unity. The Anti-Islanding Means 5 detects loss of ACutility power and blocks the feedback of AC power at the connection 15from DC sources. Power supply 2 is controlled by Digital Processor 6.Low Voltage ON/OFF control 7 receives signals (such as emergencysituations) from external control devices 13 via line 18 to shut downAlternate DC Source DC/DC Converter 9 or DC Isolation block 8. AlternateDC Sources 14 such as photovoltaic, wind turbines, fuel cells, etc. areconnected via line 19. The connection is shown as bi-directional sincethe alternate DC sources may require power in some off modes such as foryaw motors for wind turbines or pumps which are required at start-up offuel cells. DC Load 11 is connected via line 21 which is also shown asbi-directional wherein, on some occasions, DC loads can generate power.One example is a DC motor after shutdown which can act as a generatorfor a brief period.

External energy storage device 10 stores DC power for use in supplyingpower to the DC load and/or alternate energy source, in the event of aloss of AC power, supplementing power to DC load when required, orsupplementing power to AC system. Examples include a high voltagebattery, a low voltage battery with DC/DC converter, a flow Battery, aflywheel, and a capacitor. External Energy Device 10 is connected vialine 22. This connection is also bi-directional since a variety ofenergy storage devices require power during the charging phase. Simplechemical storage batteries such as lead acid or NiMH require periodiccharging. Flow batteries require the use of circulation pumps in thecharging process, and the motor/generator of a flywheel storage deviceis used as a motor to “charge” or spin-up the flywheel.

FIG. 1 also shows metering control module (MCM) 23, which containsvarious current and voltage sensors sampling the various sources andload points. These are all connected in a metering network, includingmetering control module 23, to digital processor 6. Central DataAcquisition and Control Unit 12 is an enterprise level digital processorwhich monitors and controls the operation from a central location.Besides soliciting sensor information from all MFPCU's, unit 12 alsomonitors the loading of the utility feeder line to the enterprise; inthis way it can be used to control the MFPCU's to limit the peak utilitypower used by adaptively sharing the power available with loadrequirements thereby reducing peak surcharges.

FIG. 1A shows a block diagram of multi-function power control unit(MFPCU) 60 which is an alternate embodiment of multi-function powercontrol unit (MFPCU) 1 of FIG. 1. There is no change to the externalblocks. In this embodiment of FIG. 1A, power isolation is handled by ACisolation block 61 right at power input 15. Thus all other blocks withinmulti-function power control unit (MFPCU) 60 are isolated from ACground, thereby eliminating the need for DC isolation block 8 andsimplifying the network.

While the various sensors for power, voltage and current are still usedin FIG. 1A, they are now directly interfaced to digital processor 6,instead of being first intercepted and pre-processed by metering controlmodule (MCM) block 23, as in FIG. 1.

Another change in FIG. 1A is that Low Voltage ON/OFF Control 7 is nowinterfaced to digital processor 6 which, in turn, controls the desiredblocks. Otherwise, the functions of multi-function power control unit(MFPCU) 60 in FIG. 1A are the same as those of multi-function powercontrol unit (MFPCU) 1 described above and shown in FIG. 1.

FIG. 1B shows a second alternate embodiment, with multi-function powercontrol unit (MFPCU) 70. One major change from multi-function powercontrol unit (MFPCU) 60 of FIG. 1A is that AC isolation has been movedout of multi-function power control unit (MFPCU) 70 as external block71. In this manner, existing transformers in the facility can be usedfor this purpose. External control device 13 now interfaces directlywith Bi-Directional Control Module 3, bypassing digital processor 6entirely, and eliminating the need for Low Voltage ON/OFF Control block7, as shown in FIG. 1A. In some environments, the more direct controlenhances the safety of the installation especially relating to lockingout of the ability to feed back power to the AC input line.

FIG. 2 shows typical current/voltage curves for solar cells at differentlevels of incident irradiation (here ranging from 82 to 140 W/cmsquared). The load line for maximum power collected is also drawn. Thestate-of-the-art control for extracting the maximum output from a solararray over varying operating conditions is known as maximum power pointtracking or MPPT. This is achieved either by a predictive open-loop orby a closed-loop control system. In the MFPCU of this invention, MPPT isimplemented by the buck/boost DC/DC converter of block 9 under controlof digital processor 6. Solar panels used with the current MFPCUgenerate from 250 to 600 volts. The operating voltage of a lighting loadis 380 VDC+/−1%. Thus alternate DC source DC/DC converter 9 willmaintain this output while the input varies from 250 to 600 VDC; this isdone in conjunction with MPPT protocols to maximize power transfer overdynamically changing conditions such as incident radiation and ambienttemperature.

FIGS. 3-5 illustrate the main power flows through MFPCU blocks and pathsfor different modes of operation.

FIG. 3 shows the most typical mode of operation for an MFPCU. Itillustrates AC sourced high efficiency lighting wherein load 11 is afluorescent light load using DC-input ballasts. Utility AC power at 15feeds into bi-directional AC/DC power supply 2 where it is converted (atunity power factor via power factor correction 4) to DC which flowstoward DC isolation block 8 (via line 16) and onward to DC lighting load11. In FIG. 3, no external storage device or alternate DC source areshown; they may simply not be implemented at this MFPCU, or they mayjust not be contributing power at this time.

FIG. 4 shows operation during a utility power outage. Power to supply DCload 11 is supplied via line 21 by alternate DC source 14 via line 19through DC/DC converter 9 and by external storage device 10 via lines 22and 16 through DC isolation block 8. Note that bi-directional powersupply 2 is not involved in this operation since it is shut down byanti-islanding means 5.

FIG. 5 shows a multi-MFPCU enterprise operating so as to reduce powerdemand from utility feeder 43 entering distribution panel 44. Centraldata block 12 is sampling demand via line 45. Via network ofbi-directional data lines 17, it can keep track of the status of eachMFPCU. The distribution of utility power to each MFPCU is shown as asingle line 46 (for simplicity) although multiple branch lines wouldprobably be used. In this example, DC load 42 has heavy demand fromMFPCU 32.

MFPCU 31 has its load shut down, but its storage device 41 has somecapacity. MFPCU 30 is supplying its own load 11, but its storage device10 has some capacity, and currently its alternate DC source 14 hascapacity in excess of load 11 demand. Central data block 12 is aware ofthe status of each MFPCU and the impending peak utility demandthreshold, therefore a peak “shaving” protocol is automatically entered.The bi-directional power supplies 2 of MFPCU's 30 and 31 are placed ininverter mode to feed back AC derived from DC sources via lines 47 and48 respectively. This AC is combined with utility AC on branch lines 46to supply heavy load 42 attached to MFPCU 32 via line 49. Note thatbi-directional power supply 2 in MFPCU 32 remains in rectifier mode.Obviously there are an almost infinite number of similar scenarios thatare possible on a second by second basis; this just illustrates apossible snapshot where AC is wheeled within the enterprise from oneMFPCU to another.

In the foregoing description, certain terms and visual depictions areused to illustrate the preferred embodiment. However, no unnecessarylimitations are to be construed by the terms used or illustrationsdepicted, beyond what is shown in the prior art, since the terms andillustrations are exemplary only, and are not meant to limit the scopeof the present invention.

It is further known that other modifications may be made to the presentinvention, without departing the scope of the invention, as noted in theappended Claims.

1. In a power sharing system in a DC load environment having: a sourceof AC; an alternative source of DC; a power controller capable ofinputting voltage regulated DC power simultaneously from said sources,said alternative source of DC making a shared contribution of powerselected by said power controller, and having a power junction means fordelivering a regulated voltage DC to a DC compatible load at an outputof said power sharing system; said power controller controlling supplyside power sharing to a DC load side; said power controller having aconverter converting AC inputted electrical power into a definedDC-regulated voltage to provide and manage power to said DC compatibleload; said power controller producing voltage regulated power bycontrolling response of said alternative source of DC power; said powercontroller capable of altering the output voltage of said power junctionmeans for directing power from said secondary sources of DC power tolimit peak power supplied from said source of AC power to said DCcompatible load in accordance with a pre-set threshold of power fromsaid source of AC power in order to minimize peak power surcharges;wherein the improvement comprises: means for operating said alternativesource of DC in a dynamic manner allowing maximum power generatingcapability of said alternative DC power source at specific operatingconditions of the moment; means for delivering power from saidalternative primary power source of DC in excess of that required bysaid DC compatible load back to said source of AC; and means within saidpower controller for isolating said power controller from said source ofAC.
 2. The power system of claim 1 wherein said DC compatible load isselected from the group consisting of: a lighting system, a DC powerconsumption device; a lighting ballast; a lamp; solid state lighting; aDC motor; an AC motor with variable frequency drive (VFD); and/or aninverter.
 3. The power system of claim 1 further comprising an externalDC energy storage device.
 4. The power system of claim 1 wherein saidalternative source of DC is at least one of a photo voltaic energysource, a cogenerator, a wind energy conversion system and/or a fuelcell.
 5. The power system of claim 1 wherein said source of AC is atleast one of a utility AC grid; a generator and/or a stand aloneinverter with a connected DC source.
 6. The power system as in claim 3in which said power controller contains circuitry for combining powerfrom said alternative source of DC and said external DC energy storagedevice, in the absence of power from said source of AC.
 7. The powersharing system as in claim 6 further comprising a means to stopdelivering of said DC to said AC source.
 8. A power sharing system in aDC load environment including: a source of AC; an alternative source ofDC; said power sharing system comprising: a bi-directional isolatedpower supply for converting power from said source of AC to DC power;means for operating said alternative source of DC in a dynamic mannerallowing maximum power generating capability of said alternative DCpower source at specific operating conditions of the moment; a DCcompatible load; a converter for transforming the output of saidalternative source of DC to a voltage level suitable for use by said DCcompatible load; a metering module for receiving data relating to powerfrom said converter; providing data to a digital processor to controlsaid bi-directional isolated power supply, to provide power forsupplementing power insufficiency delivered by said converter, therebysupplying load requirements of said DC compatible load, said powersystem module including means for feeding back to said source of AC,through said bi-directional isolated power supply, power delivered bysaid converter, in excess of that required by said DC compatible load atany given time; and means within said power controller for isolatingsaid power controller from said source of AC.
 9. The power system ofclaim 8 wherein said DC compatible load is selected from the groupconsisting of: a lighting system; a DC power consumption device; alighting ballast; a lamp; solid state lighting; a DC motor; an AC motorwith variable frequency drive (VFD); and/or an inverter.
 10. The powersystem of claim 8 further comprising an external DC energy storagedevice.
 11. The power sharing system of claim 8 in which saidalternative source of DC is at least one of a photovoltaic energysource, a wind energy conversion system, a cogenerator and/or a fuelcell.
 12. The power system of claim 8 wherein said source of AC is atleast one of a utility AC grid; a generator and/or a stand aloneinverter with a connected DC source.
 13. The power sharing system ofclaim 10 having an external DC Storage device to supply DC power to saidDC compatible load when there is a failure in said source of AC and saidalternative source of DC produces insufficient power for said DCcompatible load; said system also having a means for feeding back ACpower in excess of that required by said DC compatible load at any giventime from said external DC energy storage device into an AC inputconnection when AC power source is operational.
 14. The power sharingsystem as in claim 8 further comprising a means to prevent feeding backof said AC.
 15. A multiple bi-directional input/output power controlsystem comprising: at least one power control unit having a network offunctional blocks housed in a single enclosure, said unit providing DCpower to at least one DC load, said unit providing control and internalpathways sharing a plurality of power inputs, said inputs including: anAC power source, at least one alternative DC power source, and, saidunit having a means for feeding back AC power from said at least one DCpower source into an AC input connection and for isolating said unitfrom said AC power source.
 16. The multiple bi-directional input/outputpower control system as in claim 15 further comprising at least oneexternal DC energy storage device.
 17. The multiple bi-directionalinput/output power control system as in claim 15 wherein said at leastone power control unit is a plurality of interconnected power controlunits.
 18. The multiple bi-directional input/output power control systemas in claim 15 where said functional blocks are selected from the groupconsisting of: at least one hard wired electronic circuit board;software running on an internal digital processor, and/or as acombination thereof.
 19. The multiple bi-directional input/output powercontrol system as in claim 15 wherein said network of functional blocksincludes a digital processor, a low voltage ON/OFF control block, analternate DC source DC/DC converter, a DC isolation block, and abi-directional AC/DC power supply with a bi-directional control module,power factor correction means, an anti-islanding control block, andmetering network including metering control module wherein: said digitalprocessor controls said functional blocks and gathers data from saidmetering network and metering control module; said alternate DC sourceDC/DC converter conditions output of connected alternate source to matchpower requirements of said DC load; said low voltage on/off controlblock permits direct external control of said DC isolation and saidalternate DC source DC/DC converter; and, said bi-directional AC/DCpower supply providing connection to said source of AC for at least oneof the following functions: to provide power, with said power factorcorrection means to said DC connected load, and/or to feed back AC poweras directed by said bi-directional control module, with conditioningintervention by said power factor correction means, and safety interlockcontrol by said anti-islanding control block.
 20. The multiplebi-directional input/out power control system as in claim 16 whereinsaid at least one power control unit operates said alternative DC powersource in conjunction with said AC source of power and/or said externalDC energy storage device, in a dynamic manner allowing maximum powergenerating capability of said alternative DC power source at specificoperating conditions of the moment.
 21. The multiple bi-directionalinput/output power control unit as in claim 19 wherein said powercontrol unit delivers power, in excess of that required by said at leastone compatible load, to said AC power source, said external DC energystorage device, and/or a combination thereof both in a shared manner.22. The multiple bi-directional input/output power control unit as inclaim 15 wherein said means for feeding back AC power comprises abi-directional microprocessor-controlled power supply.
 23. The multiplebi-directional input/output power control unit as in claim 19 whereinsaid DC-to-DC Converter is a buck/boost converter with dynamic voltagecontrols.
 24. The multiple bi-directional input/output power controlunit as in claim 15 further comprising a DC-based meter, said metermonitoring at least one of: AC input/output, DC input/output, and/or,internal voltages and currents.
 25. The multiple bi-directionalinput/output power control unit as in claim 19 wherein saidbi-directional AC/DC power supply includes an AC/DC converter receivingat least one signal from said digital processor, and performing at leastone function of the following functions: 1) rectifying AC and providingregulated DC voltage via DC isolation when required by said at least oneDC load and/or said alternate DC power source; 2) rectifying AC andproviding regulated DC voltage to said external DC energy storagedevice; and, 3) inverting DC power from said alternate DC power sourceor said external DC energy storage device and sending said DC power backto said AC power source.
 26. The multiple bi-directional input/outputpower control system as in claim 19 wherein said power factor correctionmeans adjusts a power factor of said power control unit to apre-determined specified value.
 27. The multiple bi-directionalinput/output power control system as in claim 19 wherein saidanti-islanding means includes an analog and/or digital logic circuitdetecting loss of connection to said AC power source grid and/orexternal synchronization source.
 28. The multiple bi-directionalinput/output power control system as in claim 19 wherein saidbi-directional control module includes an analog and/or digital logicdevice enabling said bi-directional power supply to invert DC power. 29.The multiple bi-directional input/output power control system as inclaim 19 wherein said DC isolation block means electrically isolates DCoutput from said AC power source.
 30. The multiple bi-directionalinput/output power control system as in claim 15 wherein said at leastone DC load is selected from the group consisting of: a lighting system;a DC power consumption device; a lighting ballast; a lamp; solid statelighting; a DC motor; an AC motor with variable frequency drive (VFD);and/or an inverter.
 31. The multiple bi-directional input/output powercontrol system as in claim 19 wherein said low voltage ON/OFF controlshuts down all output circuits via at least one of a low voltage signaland/or a wireless communication device.
 32. The multiple bi-directionalinput/output power control system as in claim 19 wherein said lowvoltage ON/OFF control includes at least one variable signal dynamicallycontrolling voltage of said output circuits.
 33. The multiplebi-directional input/output power control system as in claim 19 whereinsaid alternate DC source DC/DC converter converts output of an alternateenergy source to a voltage level suitable for said at least one DC load,said converter dynamically changing operating characteristics of saidalternative energy source, permitting optimization of power transferand/or permitting interface with said alternative DC energy source. 34.The multiple bi-directional input/output power control system as inclaim 15 wherein said alternative DC energy source is at least one of: aphotovoltaic (PV) device, a wind turbine, a fuel cell, and/or an enginedriven cogeneration device.
 35. The multiple bi-directional input/outputpower control system as in claim 16 wherein said external energy storagedevice stores DC power and supplies power to said at least one DC loadand/or alternate energy source.
 36. The multiple bi-directionalinput/output power control system as in claim 19 wherein said digitalprocessor monitors and controls power delivery to and from a pluralityof power sources and loads, said digital processor providing aninterface for providing data and receiving control signals from anexternal central data acquisition and control unit.
 37. The multiplebi-directional input/output power control system as in claim 19 whereinsaid digital processor provides at least one of: 1) dynamic voltagecontrol and/or current control supplied by an alternate DC Source; 2) anON/OFF control of all output circuits; 3) an ON/OFF control for thebi-directional AC/DC power Supply; 4) dynamically change output voltage;and 5) dynamically change voltage of the DC link.
 38. The multiplebi-directional input/output power control system as in claim 19 whereinsaid digital processor controls providing at least one of: 1) volts,amps, and/or power delivered/supplied by the bi-directional AC/DC powersupply; 2) volts, amps, and/or power delivered/supplied by the alternateDC source; 3) volts, amps, and/or power delivered/supplied by theexternal energy storage device; 4) volts, amps, and/or powerdelivered/supplied by the load; and/or; 5) system status, alarms and/oroperating mode status.
 39. The multiple bi-directional input/outputpower control system as in claim 36 wherein said central dataacquisition and control unit provides central control and datacollection of data from said multiple power units, via each respectivedigital processor.
 40. The multiple bi-directional input/output powercontrol system as in claim 19 wherein said bi-directional power supplyis transformer isolated and includes a bridge topology permitting itsoperation as both a synchronous rectifier for supplying DC power and aninverter supplying AC power at its input from DC sources.
 41. Themultiple bi-directional input/output power control system as in claim 40wherein said bridge topology includes at least one of: a MOFSET switchand/or an insulated gate bipolar transistor (IGBT).
 42. The multiplebi-directional input/output power control system as in claim 39 whereinsaid central data acquisition and control unit includes an enterpriselevel digital processor monitoring and controlling operation from acentral location, soliciting sensor information from each power controlunit, said central data acquisition and control unit monitoring loadingof said AC utility power source line to said enterprise, controllingeach said power control unit to limit the peak utility power used, byadaptively sharing power available with requirements of said at leastone DC load, thereby reducing peak surcharges.
 43. A multiplebi-directional input/output power control system comprising a network offunctional blocks housed in a single enclosure, said system providing DCpower to at least one DC load, said system providing control andinternal pathways sharing at least one of a plurality of AC and/or DCpower inputs, said system feeding back AC power from said at least oneDC power source into an AC input connection, said fed-back AC powershared by other AC loads, said system operating at least one alternativesource of DC in a dynamic manner allowing maximization of powergenerating capability at respective specific operating conditions of themoment; and said system having means for isolating said power controllerfrom said source of AC.
 44. In a power sharing system in a DC loadenvironment having: a source of AC; an alternative source of DC; a powercontroller capable of inputting voltage regulated DC powersimultaneously from said sources, said alternative source of DC making ashared contribution of power selected by said power controller, andhaving a power junction means for delivering a regulated voltage DC to aDC compatible load at an output of said power sharing system; said powercontroller controlling supply side power sharing to a DC load side; saidpower controller having a converter converting AC inputted electricalpower into a defined DC-regulated voltage to provide and manage power tosaid DC compatible load; said power controller producing voltageregulated power by controlling response of said alternative source of DCpower; said power controller capable of altering the output voltage ofsaid power junction means for directing power from said secondarysources of DC power to limit peak power supplied from said source of ACpower to said DC compatible load in accordance with a pre-set thresholdof power from said source of AC power in order to minimize peak powersurcharges; wherein the improvement comprises: means for operating saidalternative source of DC in a dynamic manner allowing maximum powergenerating capability of said alternative DC power source at specificoperating conditions of the moment; means for delivering power from saidalternative primary power source of DC in excess of that required bysaid DC compatible load back to said source of AC; means outside of saidpower controller for isolating said power controller from said source ofAC; and an external control device for exerting control over abi-directional control module within said power controller for enablingthe inversion of DC power to AC power for sending back AC power to saidsource of AC.
 45. A power sharing system in a DC load environmentincluding: a source of AC; an alternative source of DC; said powersharing system comprising: a bi-directional isolated power supply forconverting power from said source of AC to DC power; means for operatingsaid alternative source of DC in a dynamic manner allowing maximum powergenerating capability of said alternative DC power source at specificoperating conditions of the moment; a DC compatible load; a converterfor transforming the output of said alternative source of DC to avoltage level suitable for use by said DC compatible load; a meteringmodule for receiving data relating to power from said converter;providing data to a digital processor to control said bi-directionalisolated power supply, to provide power for supplementing powerinsufficiency delivered by said converter, thereby supplying loadrequirements of said DC compatible load, said power system moduleincluding means for feeding back to said source of AC, through saidbi-directional isolated power supply, power delivered by said converter,in excess of that required by said DC compatible load at any given time;and means external of said power controller for isolating said powercontroller from said source of AC for allowing existing transformersoutside of said power controller to be used for such isolation.
 46. Thepower sharing system of claim 45 having an external control device forexerting control over a bi-directional control module within said powercontroller for enabling the inversion of DC power to AC power forsending back AC power to said source of AC.
 47. A multiplebi-directional input/output power control system comprising: at leastone power control unit having a network of functional blocks housed in asingle enclosure, said unit providing DC power to at least one DC load,said unit providing control and internal pathways sharing a plurality ofpower inputs, said inputs including: an AC power source, at least onealternative DC power source, said unit having a means for feeding backAC power from said at least one DC power source into an AC inputconnection; a bi-directional control module for enabling the inversionof DC power to AC power for sending back AC power to said source of ACpower; and means for effecting operation of said bidirectional controlmodule.
 48. The control system of claim 47 in which said means foreffecting operation of said bidirectional control module is an externalcontrol device.
 49. A multiple bi-directional input/output power controlsystem comprising a network of functional blocks housed in a singleenclosure, said system providing DC power to at least one DC load, saidsystem providing control and internal pathways sharing at least one of aplurality of AC and/or DC power inputs, said system feeding back ACpower from said at least one DC power source into an AC inputconnection, said fed-back AC power shared by other AC loads, said systemoperating at least one alternative source of DC in a dynamic mannerallowing maximization of power generating capability at respectivespecific operating conditions of the moment; and said system havingexternal means for isolating said power controller from said source ofAC.
 50. The power control system of claim 49 having a bi-directionalcontrol module for enabling the inversion of DC power to AC power forsending back AC power to said source of AC.
 51. The power control systemof claim 50 having means for effecting operation of said bidirectionalcontrol module
 52. The power control system of claim 51 in which saidmeans for effecting operation of said bidirectional control module isexternal of said enclosure.